1. Field of the Invention
The present invention relates to a massager and more particularly, to a spine massager, which comprises a master air bladder, two supplementary air bladders bilaterally provided at the top side of the master air bladder, and pressure switch means adapted to inflate and exhaust the two supplementary air bladders alternatively after having inflated the master air bladder to the saturated status.
2. Description of the Related Art
Conventional massaging apparatus commonly use rollers for massaging the joints of the spine. When electrically connected, the rollers are rotated and moved over a part of the user's back to massage the joints of the spine. These massaging apparatus cannot stretch the user's spine to achieve a satisfactory spine massaging effect.
U.S. Pat. No. 6,202,237, entitled “BED HAVING MASSAGE DEVICE”, provides a bed having a number of holes for receiving a number of pneumatic actuating devices, such as the air bag type or the bellows type pneumatic actuating devices. An air pump supplies a pressurized air to the pneumatic actuating devices via a number of air valves to actuate the pneumatic actuating devices to act on the users. This design cannot lift or stretch the user's spine.
U.S. Pat. No. 5,848,982, entitled “LOUNGER-TYPE AIR MASSAGER”, provides a massaging device, which comprises a lounger body including a seat portion and a backrest portion provided on the rear end of the seat portion, bags provided in the seat portion and the backrest portion and adapted to inflate and deflate when compressed air is fed thereinto and discharged therefrom, and a compressed air control device for controlling the feed and discharge of the compressed air into and from the bags. The bag in the seat portion is fixed at its rear edge portion on the backrest side to the seat portion, and the bag in the backrest portion is fixed at its upper end portion to the backrest portion. The compressed air control device changes the charging time or exhaust time for the compressed air, the capacity of each bag, or the flow resistance of a charging/exhaust pipe for each bag so as to make the bag among the bags, which is subjected to a heavier load from the body weight of a person seated on the lounger body than the other bag, has the same inflation as the inflation of the other bag after the feed of the compressed air into those bags is finished. This design of massaging device does not,stretch the user's spine by lifting it.
U.S. Pat. No. 5,792,082, entitled “A CHAIR-TYPE AIR MASSAGER DEVICE”, provides an air massage device which has inflatable and deflatable air bags for massaging a user's body part by air pressure causing an expansion and contraction of the air bags. The air bags of this design of massage device includes air bags for a neck massage, air bags for a back massage and air bags for a waist massage, air bags for a buttocks massage, and air bags-for a thigh massage. However, because this design is a chair-type, it does not lift the user's spine to give a stretch.
U.S. Pat. No. 5,170,522, entitled “AIR ADJUSTABLE BED”, provides an adjustable bed, which has a foundation for supporting an air mattress. The foundation has a plurality of pivotally connected transverse plates that are moved to bend the mattress to a desired contour and shape. Open top recesses in the foundation located below the plates accommodate bags have flexible walls. The bags are separately expandable and contractible to move the plates to selected elevated positions. The recesses hold the bags in lifting positions relative to the plates when the bags are inflated. The bags fit into the recesses when deflated to allow the plates to move to a horizontal position. The bed is equipped with a vibrator that is operable to vibrate the air mattress. This design simply works to lift the user's head and/or legs. It does not lift the user's spine to give a stretch.